The prior art discloses paper cutters including a carriage assembly mounted on a rail for translational movement across a cutting board to cut or trim various material. The rail is mounted for pivotal motion with respect to the cutting board to raise the carriage assembly above the paper sheets to allow for placement of the paper sheets to be cut. A circular blade is mounted in the carriage assembly for rotary motion of the circular blade as it passes over the paper sheets. The carriage assembly is biased to a retracted position on the rail when not in use. The carriage assembly is pushed down to move the blade into engagement with the stack of paper and then moved across the rail to cut or trim the paper. A self healing pad may be provided in the cutting board along the path of travel of the circular blade to provide a smooth cutting surface.
The above-described prior art paper cutters are not perfect and therefore can be improved in a number of ways. For example, the structural rigidity of the rail assembly of the cutters can be further increased to decrease flexure in the rail and thereby permit a straighter line when relatively long cuts are required. The cutters can also be provided with additional features designed to improve the accuracy of the cuts by eliminating the concern of stack-up tolerances which can accumulate between the various components of the cutter due to the separate manufacture and assembly of parts, and the general looseness between parts resulting from long-term use. Moreover, the self-healing pad and manner of attachment can be reconfigured to provide the pad with multiple useable cutting surfaces. In addition, the measuring indicia can be calibrated in at least two scales to increase the versatility of the cutter and eliminate the need for separate molds. These and other improvements, which will be apparent from the detailed description given hereinafter, would provide the above described types of paper cutters with enhanced cutting accuracy, increase longevity or useable life, and increased versatility.